While the Peace Corps was a truly unique and wonderful experience for me (Chile 1980-82) and while I am still in touch with folks in my rural village and have returned to visit, I would not repeat the experience having had the health struggles, pain and subsequent financial hardships due to the illnesses I acquired as a result of my service.
I had mediocre medical attention while in the field and terrible support from the Peace Corps Medical Office when I returned. My main issue has been with the US Dept of Labor who is legally responsible to us in the event of illness or injury. For my initial four years of illness my parents used their life savings and all of their energy literally keeping me alive.
But I'm still here and unfortunately after all these years still trying to move forward in my life and still get my bills paid. So, unlike Kevin, about five years ago I passed the point of feeling that my experience was worth the suffering.
I try, however, to separate my field experience with my Peace Corps country directors who were wonderful with the experience I had in Chile, which was stupendous. But my illness has affected my family and caused my parents terrible suffering and duress. Naturally, it has forever altered my life. It and the time and energy I have spent attempting to have financial and medical coverage has surpassed my physical suffering at times. There are many faults with the system.
Most volunteers however have a healthy and positive experience so if this is your dream I encourage you to go for it. No one could have dissuaded me in 1980.
My primary suggestion is that if you do go and do happen to get sick or injured that you make sure to document every part of it and get copies of all attention you receive even if in another country in another language. Get medical records and documentation. Otherwise, just take basic health precautions and stay well!